Tire deflation switch



Feb. 8, 1949. c. E. SULLIVAN '2,451,299

FIRE DEFLAION SWITCH vFiled March 24, 1947 www.

means, such as welding or the like.

Patented Feb. 8, 1949 UNITED STATES PATENT OFFICE Application March 24,1947, Serial No. 736,787

s claims. (ci. 20c-58) This invention relates to signal devices, andmore particularly has reference to a signal device attachable to anautomobile or the like, and adapted to inform the operator when thetires of the vehicle require iniiation.

The primary object of the invention is to pro vide a device of thecharacter described which is attachable to any conventionallyconstructed automobile or like vehicle using pneumatic tires, is simpleand inexpensive in design and con struction, and is unusually welladapted to inform the operator of the vehicle of any abnormal deflationof one of the tires of the vehicle as soon as such deflation reaches thedanger point.

Another important object of the invention is to provide a device of thetype described which is unusually durable, and which will not be damagedwhen a tire becomes completely deflated, even though this should occursuddenly, or when the tires strikes small objects normally encountered,such as stones or the like.

With the foregoing and other objects in View which will appear as thedescription proceeds, the invention consists of certain novel details ofconstruction and combinations of parts, hereinafter more fully describedand pointed out in the claims, it being understood that changes may bemade in the construction and arrangement of parts without departing fromthe spirit of the invention as claimed.

Referring to the drawings:

Figure 1 is an elevational view of a signal device constructed inaccordance with the invention, mounted in position adjacent the tire ofa motor vehicle, parts of the device being shown in vertical section,and electrical connection be tween the device and instrument panel ofthe vehicle being illustrated somewhat diagramf matically.

Figure 3 is a view taken on line 3-3 of Figure Referring to the drawingin detail, the letter of reference T designates the tire of the vehicle,B brake housing, A an axle, and P the instru ment panel, these partsbeing of conventional `construction and constituting no partV of thepresent invention.

Embodied in the invention is a hinge bracket 5 one end of the arms ofwhich is fixedly connected to the brake housing B, by any suitable Tothe outwardly extended arms of the bracket 5 is pivotally suspended, bymeans of pin 5, the elongated hollow housing 1. The housing 'I ispreferably tubular in form, and intermediate its ends, is provided witha stop plate 8, that is xedly secured in position within the housing byany suitable means.

igure 2 is a View taken on line 2--2 of Figure From a point adjacent thelower end of the housing 7, there is formed in the housing alongitudinal slot d, that may be terminated intermediate the ends of thehousing, and short of the stop plate 8. The housing I is also formedwith longitudinal slot I8, that is formed in the wall of the housingopposite to slot 9, and is in' opposite alignment with slot 9.

Extended into the open lower end of the holleing 1 is one end of a shaftll. The shaitll provided with a stop pin l2, the ends of which projectbeyond the 'surface of the shaft, and are received in the longitudinalslots 9 and i!) ofthe housing 1.

Between the end of shaft II, that is extended into the housing, and thestop plate 8 of the housing, there is interposed a spiral spring i3.Thus, it is seen that the shaft II may yieldabl'y .be forced upwardly inthe housing i, but upon rei moval of the forcing pressure, will bereturned promptly to its normal position, which 'has been illustrated inFigure 1, being held in such position by the spring I3, and stop pin I2bearing against the ends of the longitudinal slots 9 and I0.

The downwardly extended end of the shaft i is formed with a groove, inwhich is received the tongue i4 on one end of extension I5, theextension I5 vbeing hinged to the lower end of the shaft II forswingable movement in a line parallel to the path of the tire T when thevehicle is in the shaft II, are extended from their respective points ofconnection downwardly, so as to lie along the surface of the extensionI5, on opposite sides thereof. Thus, the springs I'I cooperate to holdthe extension I5 so as to be normally coaxial with the shaft II, and inaddition, when the extension I5 is swung in either direction ashereinbefore described, the springs serve the function of returning itpromptly to its normal position.

The free end of the extension l5 is provided with a projection that isextended toward the tire T, but is spaced slightly therefrom, so thatwhen the tirev is normally in properly inflated condition, theprojection will not be engaged by thetire. When, however, air is lostfrom` the tire,

the inner side wall thereof will bulge `adjacent Athe ground, and willapply pressure against the projection. This projection is preferably inthe that is open at top and bottom, in order to permit the lower end ofthev housing l to be extended therethrough. As shown particularly byFigure 2, the sides of the' cage i9 liezcloselry against the Wall of thehousing l, while the closed outer end of the cage is spaced from thewall of the housing. Thus, when the housing l is swung on its pivot 6,it will be moved to or away from the ends of the cage I9, While thesides of the cage inhibit movement in any other direction.

From the ends of the cage I9 are extended pins'zll, that are extendedpart way to the wall of the housing 1. Spiral springs 2|, that areconnected at one end to the ends of the cage, and tensionably engage thewall of the housing 'l on opposite sides thereof, at their other ends,are held in normally extended position by the pins Zll.l

Mounted on the outer end of the cage I9 and inwardly extended toward thehousing 'l is a switch 22, that is adapted to be actuated upon pressureapplied by boss 23 onthe housing 1. By means of wire 24 leading to theinstrument panel P of the. vehicle, the switch 22 when actuated provides'a signal, which may be in the form of. a ybulb 25 which is lit uponoperation of the switch by contact with the boss 23.

It is understood that a device such as has been described hereinbeforemay be attachable to each wheel of the vehicle, there being a.corresponding number of bulbs 25 on the instrument panel P, whereby theoperator may be informed as to which tire has become abnormally dcated.

In operation of a, device constructed in accordance with the invention,a tire which, for instance, may have a slow leak, will become. graduallydelated until the steadily increasing bulge in its side wall begins toapply pressure against the disc i8. While the vehicle is in operation,which will 'often be the case, no damage will result to the side wall byreason of its contact with the disc i8, inasmuch as the disc isrotatably mounted,

However, the pressure of the tire upon the disc Y will cause the housingT to be pivotaily swung in If a tire becomes completely deflated whilethe vehicle is not in operation, nodamage to the device will result ,byreason of the lower end thereof being brought into contact, with upwardpressure being obviously exterted thereupon, with the ground. Shouldthis occur, the shaft ll will be yieldably forced upwardly in thehousing l, inthe manner hereinbefore described.

In addition, should the tire or the extension ill t5 strike an object,such as a stone or the like,

while the vehicle is in operation, the extension l5, being mounted forswinging movement in the. line oi direction in which the vehicle ismoving, will pivot on the hinge pin I6, and after the obstacle has beenpassed, will be returned to What is claimed is:

l. As an attachment to a motor vehicle, a tireactuated switch comprisinga bracket secured to the brake housing of the wheel on which the tire ismounted, a housing pivotally connected to the bracket at one end forswinging movement in a plane perpendicular to the plane oi a tire of thevehicle, the other end being free, a shaft slidable in the housing andhaving one end extending from the. free end thereof, means pivotallyconnected to said end oi the shaft for swinging movement in a planeparallel to the plane of the. tire, and positioned relative to the sidewall of the tire for movement thereby upon deflation of the tire,whereby the free end of the housing may be pivotally moved, a cage,mounted on the brake housing, through which the free end of the housingis extended, and a contact element mounted on the cage, the contactelement being engageable by the end of the housing upon movement of thehousing for closing an electrical circuit'.

2. As an attachment to a motor vehicle, tireactu-ated switch comprisinga bracket secured to the brake housing of the wheel on which the tire ismounted, a housing ,pivotally connected to the bracket at one end forswinging movement in a plane perpendicular to the plane of atire of thevehicle, the other end being free, a shaft slidable in the housing andhaving one end extending frorn the free end thereof, means hinged tosaid end oi the shaft for swinging movement in a plane parallel to theplane of the tire', and positioned relative to the side wall of the tirefor lateral movement thereby upon deilation of the tire, whereby thefree end of the housing may be pivotally moved, and an electricalcontact element mounted on the vehicle for engagement by the free end ofthe swung housing.

3. As an attachment to a motor vehicle, a tireactuated switch comprisinga housing hinged at its upper end to a part oi the vehicle for swingingmovement in a plane perpendicular to vthe plane of a tire of thevehicle, a shaft telescoping in the housing and extending from the lower'end CLARENCE E SULLIVAN.

REFERENCES CITED The following references are of record. in the file oi'this patent;

UNITED STATES PATENTS.

Number Name y Date 1,681,608' Clark Aug. 2l, 1928 2,082,835 Kelly June8, 1937 FOREIGN PATENTS y Number Country Date 663,928 France Apr.1,51929 673,313 France Jan. 23, 1930 791,580 France ---su Sept. 30, 1935

